> ## Documentation Index
> Fetch the complete documentation index at: https://tech.ramses.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# ERC721Permit

Nonfungible tokens that support an approve via signature, i.e. permit

## Functions

### \_getAndIncrementNonce

```solidity theme={null}
  function _getAndIncrementNonce(
    uint256 tokenId
  ) internal virtual returns (uint256)
```

Gets the current nonce for a token ID and then increments it, returning the original value

### constructor

```solidity theme={null}
  function constructor(
    string memory name_,
    string memory symbol_,
    string memory version_
  ) internal
```

Computes the nameHash and versionHash

### DOMAIN\_SEPARATOR

```solidity theme={null}
  function DOMAIN_SEPARATOR(
  ) public view override returns (bytes32)
```

The domain separator used in the permit signature

#### Return Values:

| Type    | Description                                           |
| :------ | :---------------------------------------------------- |
| bytes32 | domain seperator used in encoding of permit signature |

### permit

```solidity theme={null}
  function permit(
    address spender,
    uint256 tokenId,
    uint256 deadline,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external
```

Approve of a specific token ID for spending by spender via signature

#### Parameters:

| Name       | Type    | Description                                                                    |
| :--------- | :------ | :----------------------------------------------------------------------------- |
| `spender`  | address | The account that is being approved                                             |
| `tokenId`  | uint256 | The ID of the token that is being approved for spending                        |
| `deadline` | uint256 | The deadline timestamp by which the call must be mined for the approve to work |
| `v`        | uint8   | Must produce valid secp256k1 signature from the holder along with `r` and `s`  |
| `r`        | bytes32 | Must produce valid secp256k1 signature from the holder along with `v` and `s`  |
| `s`        | bytes32 | Must produce valid secp256k1 signature from the holder along with `r` and `v`  |